<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>promise_初体验</title>
    <link rel="stylesheet" href="./index.css">
</head>
<body>
  <h1>初体验</h1>
  <button class="btn">点击抽奖</button>
  <script src="index.js"></script>
</body>
</html>